Over the last couple of weeks I have noticed a slight stumble when I floor the throttle off idle and then the car has cutout a couple of times aswell.

Anyway today it stumbled and missed and coughed and spluttered and kept dying, it would not drive at all for a while. ( I thought I was going to have to have it towed home) I kept restarting the engine then it would die running lig a pig. Then finally it cleared and I drove 2 miles home as if nothing was wrong.

So I check my plug wires which were new last year when the opti was replaced 3,500 miles ago new msd blaster coil, new O2 sensors. No arking in the dark no burnt wires nothing anywhere near the headers.
I put new plugs in last week NGK TR6's ready for when I run my Nos for the first time.

I have an MSD 6AL ignition and I read a post once on here that they eat opti's. When it's missing and holding back it really feels like when the opti went before but can it go again so soon 3,500 mile?

I scanned the car with datamaster there were no DTC codes, if anyone could take a look at it, I would appriciate it cause it to complicated for me. It seems to only do this in closed loop.

I also have a freescan log of the car during the bad running the only thing that looked odd to me was my O2 sensors seemed to be reading really low when it was running bad down in the 200 range but when the car runs normally when I blip the throttle they are up in the 900's

 

I have disconnected my MSD 6AL to see if that helps and I am going to unplug the MAF and run on speed density to see if it runs ok on the PCM data for speed density

 

So heres where I'm at I tried the car with MSD 6AL and MAF disconnected. I thinking if it happens only in closed loop then lets runs in speed density. it ran perfect for my 4 mile journey to work. So I reconnect my MSD 6AL and again it ran perfect.

My SES light and high speed fans were on all the time but no stumble or cutting out and the cars feels as strong as hell in speed density.

So this must mean my Opti is ok right?

So what other sensors are not used when you unplug the MAF, I know O2's are ignored but what else.

Or should I just get it tuned for speed density and forget about all those other sensors it runs so strong now with Mad Wolfs tuning.

I have moved my post to this section for obvious reasons, I can be such a dork sometimes!

HELP! COME ON YOU GUYS ARE YOU OUT THERE!

Injuneer, Shoebox, Mad Wolf

No one knows Jack about these cars over here! UK

 

After searching the message board for hours I decided to put my old ported MAF sensor in after give it a clean with some fuel injector cleaner and a cotton bud.( I don't want to touch the good one!) I plugged the MAF back in. Test drive I still got the hesitation it went to die on me while was idleling about 500rpm then it surged upto 2000 rpm without my foot on the throttle so I pushed it into nuetral.

I disconnected the MAF again and tried it runs perfect and boy does it feels strong if leaves a black stripe on the road at 30mph when it changes from 1-2 gear. ( just put 3.73's in 2 weeks ago!)

Is my custom tune completely ignored in Speed density or do I still get the firmer gear changes form the slightly increased presure for my 52mm t/body.

Cause it sure feels like the better pressure is there!

How long can I run the car in speed density? I see some of you guys run like that all the time.

Is there anyway of turn off my SES light and high speed fans can this be done in my custom tune?

 

Today I drove the car in speed density mode still, & it did something strange I was at a junction coming to a halt but the revs would not go down to idle rpm it was staying around 2,000 rpm so I pushed it into neutral. I blipped the throttle and it came back down to tickover revs and I carried on as normal.

Now I'm thinking could it be my TPS playing up, because I'm getting a stalling and serging problem.

I could sure do with some imput, someone must have had this happen to them!

Help Anyone!

 

Yes, I'm bringing this back from the dead.

Did you ever figure this problem out? Sounds EXACTLY like my problem. My motor runs great in open loop too. Maybe someone else can chime in too???

 

Hi it was my opti crap! I put a new one in and it cured everything. The opti crap can cause all sorts of running problems, eventually the car would not even drive it kept cutting out so I parked it up and took the opti out and order a brand new one form a guy in FL for $225. I here that Summit Racing are doing there own opti.

Cheers Andy